Alright I picked up an l99 long block for my next build. It's going in an 02 ws6 so I will be converting it to an ls3. Been doin a bunch of research on heads and cams. I plan on porting and polishing the heads and running a fast 102 intake as well as the 102 t/b and maf. My goal is to get past 500rwhp! So I've read a lot about the g6x3 and the tsp 231/236 camshafts. So From what I've read, ppl are afraid of the g6x3 because of ptv issues. My question is since the l99s come fly cut from the factory, with a set of ls7 lifters wouldn't this NOT be a problem with the g6x3? And should I be looking at bigger cams do to this?

 

I already looked into this. You will need to flycut on the intake side. Only the exhaust side has the valve reliefs from the factory. G6X3 is a great cam and can hit 500 on a stock cubed LS3 but it takes the best parts and milling the heads for more CR.

 

Got any idea why gm only cut the exhaust side?

has anybody else on here tried the g6x3 or tsp 231/236 in an l99?

 

I ran the g6x3 cam with some l92 heads. the cam was pretty good. Sounded good, pulled nice and had some nice grunt in the 3k rpm range. I remeved it for a custom cam from Pat G and that was a better performing cam. If you can,i would get with Pat G for a custom.

 

Its for the VVT the L99 & L92 came with. I read that it was done so you could have the pistons work for either side of the engine. That's why the reliefs are caddycorner from each other. But either way, its the exhaust side so you'd still need to flycut the intake side. I'm going to have my stock L92 heads milled .040" and flycut the intake side .080"

I was looking at the G6X3 but I think Im going to go with the EPS 231/238 113+2 cam. It makes really good power and its not as radical as the G6X3.

 

i ran the g6x3 on a l92 6.2 out of a tahoe with cnced prc l92 heads. stock bottom end unmilled heads. no fly cutting in a 6speed c5 ran 10.90 @128 1.57 60ft 3300lbs

 

What stage port did you have done? intake? tb? And if you dont mind me asking how much pwr were you puting down?

 

Cam swaps on the lt1 that's not even out yet...you guys are good...oh wait...

 

when i had the heads done there wa no stages. it was like 1500buck loaded heads with springs form texas speed. ls3 intake and tb that i ported. i had f.i.c. punch the injectors to 60lbs, 1/3/4" lg headers and tuned my self running speed density. i had it on the dyno once for two pulls when i just had got it running. was around 414 on a conservative mustang dyno. was missing timing had the maf. still rich unported intake.

 

 

he should probably not mod it... ya know... for his safety

 

Big gunz in the house!

Esp since it's obviously too much power for the GM engineers to handle. Big gunz was probably the one who wrecked it already.

 

I am also intersted in this, would I have to flycut the pistons on an LS3 vette with the G6x3 cam. What about a 227/239 from 21 century muscle, I heard this cam also went to 500 rwhp but the lift is like .629

 

If you dont mill the heads or run a thinner than stock head gasket, I believe you can run the G6X3 without flycutting. You could probably get away with milling .010-.020" off the heads with the 21st Century cam, but this is just my guess. Id call them and confirm that. They would know.

 

i run the lg g6x3 with my ls3 camaro. its a pretty aggressive cam for a dd car. i talked to lg about doing some head work and they said that the ptv is alrdy superclose and i couldnt mill the heads with flycutting. my car made 472/432 in 106* shop temps and had a shitty tb port job that cut back a few hp. they are guys thats made close to 500rwhp with the cam only. but if i had it to do over i would get a custom grind from patt g. just for the simple fact that u can get the same hp and still be able to mill ur heads without flycutting and make that 500 rwhp mark.

my car tho anything below the 3500 rpm mark is pretty bad . i mean it will pull but when u get above that the car picks up alot.

i also asked about the thinner gasket and that was a no go lg said. but i have heard some ppl say that they could but i wouldnt do it .